undefined symbol for 64 bit version only

[Wolfgang]

Hi,

it sounds like this simple question of the linker missing an undefined symbol, however...:

• the project compiles fine in Debug mode, Debug64 mode, and also in Release mode - the linker complains only in Release64 mode
• I deleted the cvibuild folder and rebuilt everything, same result
• in the file where the variable seems unknown I have several variables defined as external, all work except this one, and all work if compiled as 32 bit executable. To be more precise, the declaration in file B is:
  

  extern int main_menubar_handle;

  extern double robust_statistics_resolution;

  Both variables are defined in the same file A. Only the second variable throws the linker error. Could it be a memory issue of the 64 bit linker?

The project has no external libs or dlls, just my own source code files. I am using CVI2020.

Any hints or suggestions?

Thanks!

[Wolfgang]

Dear All,

I have gained some more insight into this issue:

the linker error is gone if I remove the check mark "Enable OpenMP_support".

An undefined symbol error should not be caused by enabling this option, so now I tend to call it a bug in CVI.

Workaround:

• don't build 64 bit executables or
• don't use OpenMP or
• don't use large projects

Unfortunately, for my project this is not an option, so I hope for a quick patch... Please, NI...

[Wolfgang]

In the mean time the bug has been reproduced at NI, thanks, Hamlet.

The bug report has the number 1244936

[Razvan_P]

Hi Wolfgang,

Is it possible that robust_statistics_resolution is not used at all in the file where it is defined? 

If that is the case, can you try to used it somewhere in that file? Maybe create a local varialbe in a function and initialize it with robust_statistics_resolution value.

[Wolfgang]

Hi Razvan,

thanks for looking into it and your suggestion, however, the variable is used in the file where it is defined.

Also, you should be able to have a look into the source code, I have sent it to NI for helping your colleagues reproduce the error. You might ask Hamlet where it went, he was the support engineer taking care of this case, but I also could send it to you via PM if needed.